Orange County would pay nearly $317 million, including a 16.5 percent share of the construction costs and 18.5 percent of the interest.

A public-private Funding and Community Collaborative has offered to pay the remaining 2 percent of local construction costs through donations of cash and land. The group’s share is not guaranteed, but its goal is $100 million.

Orange County’s decision comes ahead of the Federal Transit Administration’s April 30 deadline for moving the project into engineering. That’s the next step in applying for a federal grant to cover half of the total $2.5 billion construction cost. The state is being asked to pay up to 10 percent.

The local cost includes interest on planned loans through 2062. It would be paid using proceeds from a half-cent sales tax, car rental fees and registration fees.

If the anticipated state or federal funding falls through, the agreement requires the counties to meet with GoTriangle and consider other solutions. Project officials have said light rail won’t be possible without federal funding, which President Donald Trump targeted earlier this year in his proposed federal budget.

Light rail construction is slated to begin in 2020 with a launch in 2029.

Chapel Hill’s role

The Chapel Hill Town Council sent a letter to the commissioners this week supporting light rail and seeking a more direct role in regional transit planning. Two members – Nancy Oates and Jessica Anderson – rejected the letter because of concerns about the light-rail project’s cost.

The council also urged more bus hours to serve the light-rail stations. Chapel Hill Transit and its regional partners will start planning those services this summer, the letter states. While UNC pays for most bus service in the rail corridor now, transit officials aren’t sure what UNC will pay when light rail is launched.

“Foundational to our future plans has been the ability of Chapel Hill Transit to serve as the backbone of local service and as a connector to regional transit providers,” the letter states. “With this in mind, we wish to advocate for increased financial resources for the Chapel Hill Transit system which are necessary to meet future growth demand, to connect riders to station areas and to make essential ‘last mile’ connections.”

The town also asked for $37.7 million in regional funding for its $125 million Bus-Rapid Transit route on Martin Luther King Jr. Boulevard. The transit plan only pays $6.1 million.

GoTriangle, Orange County and the regional Durham-Chapel Hill-Carrboro planning group could renegotiate the agreement for adding transit services, said Jeff Mann, GoTriangle’s general manager. He suggested they meet with Chapel Hill Transit’s partners – Chapel Hill, Carrboro and UNC – before June 30.